IBDP Computer Science A2.3 Data transmissions HL Paper 1 - New Syllabus
▶️ Answer/Explanation
Any two valid characteristics may be identified. For example:
• High bandwidth and fast data transmission: Fibre-optic cables can carry large amounts of data at very high transmission rates.
• Low susceptibility to interference: Because data is transmitted as pulses of light rather than electrical signals, fibre-optic cables are resistant to electromagnetic and radio-frequency interference. This makes signal transmission more reliable.
Other acceptable characteristics include:
• low latency;
• large data capacity;
• secure transmission;
• relatively low signal attenuation over long distances;
• greater installation complexity than many copper cables;
• higher cost than some other transmission media.
Answer: Fibre-optic cables provide high-bandwidth, high-speed data transmission and are resistant to electromagnetic interference.
▶️ Answer/Explanation
(a) Different levels of access can be implemented by assigning each user a role, such as administrator, teacher, student or guest.
Each user can have a unique username and password, with authentication required before accessing the system. Additional security could include two-factor authentication (2FA).
The administrator role can have full access to system resources and permissions, including managing users and services.
Teachers can have access to resources required for teaching, such as student grades and authorized student information, while being prevented from accessing confidential financial information that is not relevant to them.
Students can have access only to their own files, reports or assignments and should not be able to access other students’ or teachers’ private information.
Guests can have very restricted access, such as internet access only, with no access to files containing personal, health or financial information.
Alternatively, VLANs can be used to segment different groups, with access control rules determining which resources each group can access.
Answer: Assign users to roles, authenticate them using usernames/passwords or MFA, and give each role only the permissions required for its activities.
(b)(i) One suitable communication link is fibre-optic cable.
Fibre-optic transmission provides high transmission speeds and is reliable for high-speed internet access.
Other accepted answers include 5G wireless broadband, satellite links and coaxial cable, provided an appropriate justification is given.
Answer: Fibre-optic cable because it provides fast and reliable data transmission.
(b)(ii) Two suitable security measures are:
• Enable a firewall: The firewall can monitor and filter incoming and outgoing network traffic and prevent unauthorized connections.
• Use encryption: If attackers gain access to network traffic, encryption makes the sensitive information difficult to understand without the appropriate key.
Other accepted measures include MAC address filtering, regular software updates, antivirus software, anti-spyware software, MFA, VPNs and user security training.
Answer: Use a firewall to filter unauthorized network traffic and encryption to protect sensitive data from interception.
(c) Three possible problems are:
• Emails may use up available storage, particularly if many messages or large attachments are stored.
• Large numbers of emails or large attachments may consume network bandwidth and overload the internet connection.
• Students or teachers may be exposed to phishing attacks or malware through malicious links or attachments, potentially compromising accounts or spreading malware across the network.
Other accepted problems include cyberbullying, cheating, inappropriate content, inappropriate personal use, increased IT workload and increased costs.
Answer: Possible problems include storage consumption, increased network traffic and security threats such as phishing and malware.